20728433 has 8 divisors (see below), whose sum is σ = 22766400. Its totient is φ = 18716080.

The previous prime is 20728427. The next prime is 20728439. The reversal of 20728433 is 33482702.

It is an interprime number because it is at equal distance from previous prime (20728427) and next prime (20728439).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20728433 - 2¹⁰ = 20727409 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20728396 and 20728405.

It is not an unprimeable number, because it can be changed into a prime (20728439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4685 + ... + 7962.

It is an arithmetic number, because the mean of its divisors is an integer number (2845800).

Almost surely, 2^20728433 is an apocalyptic number.

It is an amenable number.

20728433 is a deficient number, since it is larger than the sum of its proper divisors (2037967).

20728433 is a wasteful number, since it uses less digits than its factorization.

20728433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12807.

The product of its (nonzero) digits is 8064, while the sum is 29.

The square root of 20728433 is about 4552.8488883335. The cubic root of 20728433 is about 274.6979957339.

The spelling of 20728433 in words is "twenty million, seven hundred twenty-eight thousand, four hundred thirty-three".